Lifting jack



sem. 1s, 1923. MMM@ M. D. RIKER LIFTING JACK Filed nec. 2s. 191s Patented Sept. 18, 1923.

MALCOLM D. R1

TESL KIIEBI,v OF DOVER, NEW ERSEY, ASSIGNOR 'LOV IIoKIERNAN-TERRY DRILL COMPANY, A CORPORATION OF NEW JERSEY.

. LIFTING JACK.

Applicationlled December 2G, V1918. Serial No. 268,348..-

To all, whom t may concern.'

. Be it know'nzthat I, MALCOLM D. RIKER,

afcitizen of the United States of America, Y

and a resident of Dover, vcounty of Morris, 5, and State of New Jersey, have inventedcer.- tain-new and useful Improvements in Lifting'Jacks, of which the following isla speci-4l ficatioii, `reference being had to` theaccompanying drawings, formingfa partthereof- This inventionrelatesto new and useful improvements iii lifting jacks of -the screw type, and .its object-is to provide a simple,

inexpensive and eiiicient device of this character which is bothgstrong and light. j In order that my invention may be thoroughly understood, l willinow proceed to describe the same in the following specification,1and will -then point out theV novel features thereof in appended claims, j

Referring to the drawings: i Y i Figure 1 is a sectional elevation of a jack made `according to and embodyingthis inA vention, the section being takenoii the line 1-1 of Figure 2. Figure 2 is a similar View taken at right angles to the View shown 2in Figure `1 or on the line 2-2 of the Vlatter figure. Y Y* 4Figure 3 is a sectional plan view on the line'` 3 3 of Figure l. 'Y 1 1 f Figure 4. is asectional plan view Von,the line 4-4 of Figure 1.1 l i,

Figure 5 isa sectional plan View on the line 5-5`of Figure 1.` j Like charactersv of corresponding parts in all the figures.

' `10 designates a base-of cast or forged metal, which has an upstanding integral collar. This, as shown,in Figure 4, is a continuous part composedoftwo portions 11-.11V which are, semi-cylindricalV and intermediate lflat parallel sides 12-12.

An innershell 13 is welded or otherwise afiixed to this :base The inner shell -is a cylindrical tube which from diametrically opposite parts14`to its lowerendg. is flatA tened to a cross-section shapelcoiresponding in form with the collarl-l, 12 but sufficiently larger to iit over the 'collar'to which it is affixed( The flat parallelv sidesofthe inner shell are designated-.by the reference numerals 15-15, and its upper cylindrical portion by the reference'numeralV 16,

17 is `an outer shellfof; cylindrical form which lits slidably over thepart ltof the inner shell. VNear its lower -end'it is fiat `reference designateV tened at 18 to form fiat sides 19-19 which lit over the flat parts 15 of the inner shell.

20 is the headof' the device which is screwed unto the upper end of the outer shell 17 and into its upper end is screwed the engaging plate 21. There is a circular recess 'in the center of the under side of the engaging plate into which fits the upper reduced end 22 of the lifting screw 23 which is preferably made hollow as shown at 24. lThe thin wallsof the shells permits the use of agllifting screw` ofcomparatively larger diameter,Y and of consequently greater strength, than is possible with such construe.- tions as have beenavailable heretofore.

A worm gear 25`is keyed or otherwise affixed to the lifting screw and a worm 26 which has bearingsgin the head 2O is in mesh with it. 27 is a thrust member surrounding the end 22 of the lifting screw and interposed hetweentheupper end of the worm gear 25 and the engaging plate21.

A stationary nut 28 provided'with internal threads with which Ythe lifting screw engages, is fitted in the upper' cylindrical part 16 of the inner shell. .The lower end of this nut is flattened on opposite sides as at 29 to fit into the flattenedpart of the inner shell which prevents the nut from turning. i

When the worm :26 isV turned in one direction, the lifting screw is rotated in the nut and raises the head 20 and the parts connected with it. Thismovement may be contiiiued until theA parts 18 of the outer shell come in Contact with the parts 14 of the iuner shell. This limits the lift of the jack and as these parts 18 and 14 are beveled surfaces they form an effective stop without jamming the metal. f

The ack herein described is very light for its strength. It is easily constructed of few parts and needs but little machining. The inner and outer shells are Ymade of commercial tubing, pressed into desired shapes. These may be made in quantities, kept in stock and cut off at desired lengths to malte jacks of different sizes. vThe flattened sides of the shells effectively prevents relative rotation.. This eliminates one of the objectionable features of worm drivenlscrew jacks and permits the use of a steep pitch of thread on the lifting screw.

A structure of preferred form `and construction has been illustratedand described Litera Yio ` shoulders lbeing arranged to limit the Y A Y'ais upper portion Withan externalcylindrical for the purposeof-showing a 'Way in which this invention may be used, but the inventive Vthought upon which this application is based tively sliding said members, said shoulders beingarranged to limit the lextent of such relative movement. i

2. A lifting jack comprising two tubular members 'each Vhaving cylindricalA por-tions engagingl each other, portions vwith flattened engaging surfaces, and beveled shoulders betiveenthe cylindricalfportions and the portions `With' flattened surfaces, and means Y for relatively sliding said members, saidbeveled eX- tent ,of such relative movement.

3. A lifting jack "comprising lan inner member 'having a comparatively short upper portion with an external cylindrical surface, and a longer portion having a flat side, ,anouter' member having a comparatively long portion With an internal cylindrical surface lit-ting v`the cylindrical Aportion of the innermember and a shorter portionV having -a flat side engagingthe flat side Aof the inner member, and means for relatively sliding said members. 'Y Y Ll. A lifting jack-'comprising 'an inner tu' bular member having a comparatively short upper portion ivi-th an external cylindrical surface, and a longer portion having 'fiattened surfacesyan outer tubular memberliaving a comparatively long portion with an in! ternal cylindrical surface fitting the cylindrical portion ofthe inner member and a shorter yportion having flattened `surfaces l:en-

gaging the flattened surfaces ofV the inner member, and means for relatively sliding said members. i v

5. A lifting jackVV comprising 'an inner'tubular member having a comparatively Ashort surface, and a longer portion `having fiat-tened surfaces, an Vouter tubular' member having a comparativelylong portion with an internalcylindrical surface fitting the cylin- `drical portion of the inner Vmember and a shorter portion havingl flattened surfaces engaging the flattened surfaces ofthe inner member, means for relatively sliding said c members, :and a base having a part fitted into and affixed to 'the lower end of 'said in? ner member.

' ranged to limit the extent unlike portions ofv their lengths to prevent member having-'at the-end of ,its depressed i part a shoulder, niea'nsfor relatively slid'- ing said members, said shoulders being arof said V,relative sliding movement.

'7. A-liftingr jack :comprising two members of commercialtubing having engaging surfaces, parts of the engaging surfaces of both Y of said mei'nbersbeing depressed throughout unlike portions of their length to VpreventV relative rotation ofthe. members, and eachV Y. Y

part abeveledshoulden and-means for rela` i; tively VVsliding said members, said c beveled shoulders being arranged to limit the-extent.'

of said relativer-'sliding movement.V

18; A' lifting `jack comprising two fmein-.

bers of commercial tubing. having 'engaging surfaces, parts of themengaging surfaces of' both of j said members being depressed throughout unlike portions 3 offtheir. lengthsy to prevent relative rotation `o'fjthe inembers, and eachV member having-ast the end of its depressed" parlt fa shoulder," rotative-means for relatively sliding .saidl.members,i said shoulders beingarranged to limit the eX-tent of said lrelative sliding movement;

9,. A lifting v'jfaclr comprising twofmembers of commercial tubing having engaging Y surfaces, parts of 'theenga-ging surfacesof both of said members being" depressed throughout unlike yportions ofrtheirV length to prevent relative rotation off the `niembers, and each memberhaving Yat-the endico of its depressed parta beveled shoulder, and Y Y rotative means for 'relativelyfsliding said members, said-beveled .shcmlders'V being'arfsaidrelative Y ranged to limit the extent of sliding movement. Y i

10. A lifting` jackconrprivsling tivemem` bers of commercial tubing 'havin'giiengaging surfaces, parts of the-engaging surfaces .Tof both Y :of said members being #depressed th-rouglfiout .unlike Y. p ortion-s fof jtlreir lengths to prevent relative rotation of the members, Y and each member Shaving atV 1the.end of `its depressed parta shoulder, the-said shoulders belingarrangedto limit'the 'extent of said relative. slidingV movement, la ibase aiiXed to the lovver end hofthe innerof -said members, af'nut connected" W'itlyi the upper xend :of the inner said member, a tscreav Vengaging saidnut androtatively connected Vwith the outer of sai-d members, .andmeans for rotating fsaid 4screw.V

v11. Afflifting Vjack `comprising teleseop-V ically engaged Y members of standard com..

Vmercial `tubing o -of initially uniform: cross section slidingly fitting `one cnferjithey other lengths of such members to prevent relative rotation of the members and to provide stop shoulders at the commencement of Such deformed portions engaging to limit the sliding movement of one member over the other and means for relatively sliding the members. i

12. A lifting jack comprising an inner member having a longitudinally short portion with an external eiroumferentially continuous cylindrical surface and a longie tudinally longer portion With a Hat side;

an outer member having a longitudinally long portion with an interna-l circumferentially continuous cylindrical surface with which the cylindrical portion of the inner member forms a sliding lit, and a longitudinally shorter portion with a flat side forming a sliding engagement with the long lat side of the inner member, and means for relatively sliding said members.

In Witness whereof, I have hereunto set my hand this 2l day of December, 1918.

MALCOLM D. BIKER. 

